diff options
Diffstat (limited to 'arch/arm/mach-omap1/clock.c')
| -rw-r--r-- | arch/arm/mach-omap1/clock.c | 609 |
1 files changed, 609 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/clock.c b/arch/arm/mach-omap1/clock.c new file mode 100644 index 00000000..84ef7047 --- /dev/null +++ b/arch/arm/mach-omap1/clock.c @@ -0,0 +1,609 @@ +/* + * linux/arch/arm/mach-omap1/clock.c + * + * Copyright (C) 2004 - 2005, 2009-2010 Nokia Corporation + * Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com> + * + * Modified to use omap shared clock framework by + * Tony Lindgren <tony@atomide.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/clkdev.h> + +#include <asm/mach-types.h> + +#include <plat/cpu.h> +#include <plat/usb.h> +#include <plat/clock.h> +#include <plat/sram.h> +#include <plat/clkdev_omap.h> + +#include "clock.h" +#include "opp.h" + +__u32 arm_idlect1_mask; +struct clk *api_ck_p, *ck_dpll1_p, *ck_ref_p; + +/* + * Omap1 specific clock functions + */ + +unsigned long omap1_uart_recalc(struct clk *clk) +{ + unsigned int val = __raw_readl(clk->enable_reg); + return val & clk->enable_bit ? 48000000 : 12000000; +} + +unsigned long omap1_sossi_recalc(struct clk *clk) +{ + u32 div = omap_readl(MOD_CONF_CTRL_1); + + div = (div >> 17) & 0x7; + div++; + + return clk->parent->rate / div; +} + +static void omap1_clk_allow_idle(struct clk *clk) +{ + struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk; + + if (!(clk->flags & CLOCK_IDLE_CONTROL)) + return; + + if (iclk->no_idle_count > 0 && !(--iclk->no_idle_count)) + arm_idlect1_mask |= 1 << iclk->idlect_shift; +} + +static void omap1_clk_deny_idle(struct clk *clk) +{ + struct arm_idlect1_clk * iclk = (struct arm_idlect1_clk *)clk; + + if (!(clk->flags & CLOCK_IDLE_CONTROL)) + return; + + if (iclk->no_idle_count++ == 0) + arm_idlect1_mask &= ~(1 << iclk->idlect_shift); +} + +static __u16 verify_ckctl_value(__u16 newval) +{ + /* This function checks for following limitations set + * by the hardware (all conditions must be true): + * DSPMMU_CK == DSP_CK or DSPMMU_CK == DSP_CK/2 + * ARM_CK >= TC_CK + * DSP_CK >= TC_CK + * DSPMMU_CK >= TC_CK + * + * In addition following rules are enforced: + * LCD_CK <= TC_CK + * ARMPER_CK <= TC_CK + * + * However, maximum frequencies are not checked for! + */ + __u8 per_exp; + __u8 lcd_exp; + __u8 arm_exp; + __u8 dsp_exp; + __u8 tc_exp; + __u8 dspmmu_exp; + + per_exp = (newval >> CKCTL_PERDIV_OFFSET) & 3; + lcd_exp = (newval >> CKCTL_LCDDIV_OFFSET) & 3; + arm_exp = (newval >> CKCTL_ARMDIV_OFFSET) & 3; + dsp_exp = (newval >> CKCTL_DSPDIV_OFFSET) & 3; + tc_exp = (newval >> CKCTL_TCDIV_OFFSET) & 3; + dspmmu_exp = (newval >> CKCTL_DSPMMUDIV_OFFSET) & 3; + + if (dspmmu_exp < dsp_exp) + dspmmu_exp = dsp_exp; + if (dspmmu_exp > dsp_exp+1) + dspmmu_exp = dsp_exp+1; + if (tc_exp < arm_exp) + tc_exp = arm_exp; + if (tc_exp < dspmmu_exp) + tc_exp = dspmmu_exp; + if (tc_exp > lcd_exp) + lcd_exp = tc_exp; + if (tc_exp > per_exp) + per_exp = tc_exp; + + newval &= 0xf000; + newval |= per_exp << CKCTL_PERDIV_OFFSET; + newval |= lcd_exp << CKCTL_LCDDIV_OFFSET; + newval |= arm_exp << CKCTL_ARMDIV_OFFSET; + newval |= dsp_exp << CKCTL_DSPDIV_OFFSET; + newval |= tc_exp << CKCTL_TCDIV_OFFSET; + newval |= dspmmu_exp << CKCTL_DSPMMUDIV_OFFSET; + + return newval; +} + +static int calc_dsor_exp(struct clk *clk, unsigned long rate) +{ + /* Note: If target frequency is too low, this function will return 4, + * which is invalid value. Caller must check for this value and act + * accordingly. + * + * Note: This function does not check for following limitations set + * by the hardware (all conditions must be true): + * DSPMMU_CK == DSP_CK or DSPMMU_CK == DSP_CK/2 + * ARM_CK >= TC_CK + * DSP_CK >= TC_CK + * DSPMMU_CK >= TC_CK + */ + unsigned long realrate; + struct clk * parent; + unsigned dsor_exp; + + parent = clk->parent; + if (unlikely(parent == NULL)) + return -EIO; + + realrate = parent->rate; + for (dsor_exp=0; dsor_exp<4; dsor_exp++) { + if (realrate <= rate) + break; + + realrate /= 2; + } + + return dsor_exp; +} + +unsigned long omap1_ckctl_recalc(struct clk *clk) +{ + /* Calculate divisor encoded as 2-bit exponent */ + int dsor = 1 << (3 & (omap_readw(ARM_CKCTL) >> clk->rate_offset)); + + return clk->parent->rate / dsor; +} + +unsigned long omap1_ckctl_recalc_dsp_domain(struct clk *clk) +{ + int dsor; + + /* Calculate divisor encoded as 2-bit exponent + * + * The clock control bits are in DSP domain, + * so api_ck is needed for access. + * Note that DSP_CKCTL virt addr = phys addr, so + * we must use __raw_readw() instead of omap_readw(). + */ + omap1_clk_enable(api_ck_p); + dsor = 1 << (3 & (__raw_readw(DSP_CKCTL) >> clk->rate_offset)); + omap1_clk_disable(api_ck_p); + + return clk->parent->rate / dsor; +} + +/* MPU virtual clock functions */ +int omap1_select_table_rate(struct clk *clk, unsigned long rate) +{ + /* Find the highest supported frequency <= rate and switch to it */ + struct mpu_rate * ptr; + unsigned long dpll1_rate, ref_rate; + + dpll1_rate = ck_dpll1_p->rate; + ref_rate = ck_ref_p->rate; + + for (ptr = omap1_rate_table; ptr->rate; ptr++) { + if (ptr->xtal != ref_rate) + continue; + + /* DPLL1 cannot be reprogrammed without risking system crash */ + if (likely(dpll1_rate != 0) && ptr->pll_rate != dpll1_rate) + continue; + + /* Can check only after xtal frequency check */ + if (ptr->rate <= rate) + break; + } + + if (!ptr->rate) + return -EINVAL; + + /* + * In most cases we should not need to reprogram DPLL. + * Reprogramming the DPLL is tricky, it must be done from SRAM. + * (on 730, bit 13 must always be 1) + */ + if (cpu_is_omap7xx()) + omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val | 0x2000); + else + omap_sram_reprogram_clock(ptr->dpllctl_val, ptr->ckctl_val); + + /* XXX Do we need to recalculate the tree below DPLL1 at this point? */ + ck_dpll1_p->rate = ptr->pll_rate; + + return 0; +} + +int omap1_clk_set_rate_dsp_domain(struct clk *clk, unsigned long rate) +{ + int dsor_exp; + u16 regval; + + dsor_exp = calc_dsor_exp(clk, rate); + if (dsor_exp > 3) + dsor_exp = -EINVAL; + if (dsor_exp < 0) + return dsor_exp; + + regval = __raw_readw(DSP_CKCTL); + regval &= ~(3 << clk->rate_offset); + regval |= dsor_exp << clk->rate_offset; + __raw_writew(regval, DSP_CKCTL); + clk->rate = clk->parent->rate / (1 << dsor_exp); + + return 0; +} + +long omap1_clk_round_rate_ckctl_arm(struct clk *clk, unsigned long rate) +{ + int dsor_exp = calc_dsor_exp(clk, rate); + if (dsor_exp < 0) + return dsor_exp; + if (dsor_exp > 3) + dsor_exp = 3; + return clk->parent->rate / (1 << dsor_exp); +} + +int omap1_clk_set_rate_ckctl_arm(struct clk *clk, unsigned long rate) +{ + int dsor_exp; + u16 regval; + + dsor_exp = calc_dsor_exp(clk, rate); + if (dsor_exp > 3) + dsor_exp = -EINVAL; + if (dsor_exp < 0) + return dsor_exp; + + regval = omap_readw(ARM_CKCTL); + regval &= ~(3 << clk->rate_offset); + regval |= dsor_exp << clk->rate_offset; + regval = verify_ckctl_value(regval); + omap_writew(regval, ARM_CKCTL); + clk->rate = clk->parent->rate / (1 << dsor_exp); + return 0; +} + +long omap1_round_to_table_rate(struct clk *clk, unsigned long rate) +{ + /* Find the highest supported frequency <= rate */ + struct mpu_rate * ptr; + long highest_rate; + unsigned long ref_rate; + + ref_rate = ck_ref_p->rate; + + highest_rate = -EINVAL; + + for (ptr = omap1_rate_table; ptr->rate; ptr++) { + if (ptr->xtal != ref_rate) + continue; + + highest_rate = ptr->rate; + + /* Can check only after xtal frequency check */ + if (ptr->rate <= rate) + break; + } + + return highest_rate; +} + +static unsigned calc_ext_dsor(unsigned long rate) +{ + unsigned dsor; + + /* MCLK and BCLK divisor selection is not linear: + * freq = 96MHz / dsor + * + * RATIO_SEL range: dsor <-> RATIO_SEL + * 0..6: (RATIO_SEL+2) <-> (dsor-2) + * 6..48: (8+(RATIO_SEL-6)*2) <-> ((dsor-8)/2+6) + * Minimum dsor is 2 and maximum is 96. Odd divisors starting from 9 + * can not be used. + */ + for (dsor = 2; dsor < 96; ++dsor) { + if ((dsor & 1) && dsor > 8) + continue; + if (rate >= 96000000 / dsor) + break; + } + return dsor; +} + +/* XXX Only needed on 1510 */ +int omap1_set_uart_rate(struct clk *clk, unsigned long rate) +{ + unsigned int val; + + val = __raw_readl(clk->enable_reg); + if (rate == 12000000) + val &= ~(1 << clk->enable_bit); + else if (rate == 48000000) + val |= (1 << clk->enable_bit); + else + return -EINVAL; + __raw_writel(val, clk->enable_reg); + clk->rate = rate; + + return 0; +} + +/* External clock (MCLK & BCLK) functions */ +int omap1_set_ext_clk_rate(struct clk *clk, unsigned long rate) +{ + unsigned dsor; + __u16 ratio_bits; + + dsor = calc_ext_dsor(rate); + clk->rate = 96000000 / dsor; + if (dsor > 8) + ratio_bits = ((dsor - 8) / 2 + 6) << 2; + else + ratio_bits = (dsor - 2) << 2; + + ratio_bits |= __raw_readw(clk->enable_reg) & ~0xfd; + __raw_writew(ratio_bits, clk->enable_reg); + + return 0; +} + +int omap1_set_sossi_rate(struct clk *clk, unsigned long rate) +{ + u32 l; + int div; + unsigned long p_rate; + + p_rate = clk->parent->rate; + /* Round towards slower frequency */ + div = (p_rate + rate - 1) / rate; + div--; + if (div < 0 || div > 7) + return -EINVAL; + + l = omap_readl(MOD_CONF_CTRL_1); + l &= ~(7 << 17); + l |= div << 17; + omap_writel(l, MOD_CONF_CTRL_1); + + clk->rate = p_rate / (div + 1); + + return 0; +} + +long omap1_round_ext_clk_rate(struct clk *clk, unsigned long rate) +{ + return 96000000 / calc_ext_dsor(rate); +} + +void omap1_init_ext_clk(struct clk *clk) +{ + unsigned dsor; + __u16 ratio_bits; + + /* Determine current rate and ensure clock is based on 96MHz APLL */ + ratio_bits = __raw_readw(clk->enable_reg) & ~1; + __raw_writew(ratio_bits, clk->enable_reg); + + ratio_bits = (ratio_bits & 0xfc) >> 2; + if (ratio_bits > 6) + dsor = (ratio_bits - 6) * 2 + 8; + else + dsor = ratio_bits + 2; + + clk-> rate = 96000000 / dsor; +} + +int omap1_clk_enable(struct clk *clk) +{ + int ret = 0; + + if (clk->usecount++ == 0) { + if (clk->parent) { + ret = omap1_clk_enable(clk->parent); + if (ret) + goto err; + + if (clk->flags & CLOCK_NO_IDLE_PARENT) + omap1_clk_deny_idle(clk->parent); + } + + ret = clk->ops->enable(clk); + if (ret) { + if (clk->parent) + omap1_clk_disable(clk->parent); + goto err; + } + } + return ret; + +err: + clk->usecount--; + return ret; +} + +void omap1_clk_disable(struct clk *clk) +{ + if (clk->usecount > 0 && !(--clk->usecount)) { + clk->ops->disable(clk); + if (likely(clk->parent)) { + omap1_clk_disable(clk->parent); + if (clk->flags & CLOCK_NO_IDLE_PARENT) + omap1_clk_allow_idle(clk->parent); + } + } +} + +static int omap1_clk_enable_generic(struct clk *clk) +{ + __u16 regval16; + __u32 regval32; + + if (unlikely(clk->enable_reg == NULL)) { + printk(KERN_ERR "clock.c: Enable for %s without enable code\n", + clk->name); + return -EINVAL; + } + + if (clk->flags & ENABLE_REG_32BIT) { + regval32 = __raw_readl(clk->enable_reg); + regval32 |= (1 << clk->enable_bit); + __raw_writel(regval32, clk->enable_reg); + } else { + regval16 = __raw_readw(clk->enable_reg); + regval16 |= (1 << clk->enable_bit); + __raw_writew(regval16, clk->enable_reg); + } + + return 0; +} + +static void omap1_clk_disable_generic(struct clk *clk) +{ + __u16 regval16; + __u32 regval32; + + if (clk->enable_reg == NULL) + return; + + if (clk->flags & ENABLE_REG_32BIT) { + regval32 = __raw_readl(clk->enable_reg); + regval32 &= ~(1 << clk->enable_bit); + __raw_writel(regval32, clk->enable_reg); + } else { + regval16 = __raw_readw(clk->enable_reg); + regval16 &= ~(1 << clk->enable_bit); + __raw_writew(regval16, clk->enable_reg); + } +} + +const struct clkops clkops_generic = { + .enable = omap1_clk_enable_generic, + .disable = omap1_clk_disable_generic, +}; + +static int omap1_clk_enable_dsp_domain(struct clk *clk) +{ + int retval; + + retval = omap1_clk_enable(api_ck_p); + if (!retval) { + retval = omap1_clk_enable_generic(clk); + omap1_clk_disable(api_ck_p); + } + + return retval; +} + +static void omap1_clk_disable_dsp_domain(struct clk *clk) +{ + if (omap1_clk_enable(api_ck_p) == 0) { + omap1_clk_disable_generic(clk); + omap1_clk_disable(api_ck_p); + } +} + +const struct clkops clkops_dspck = { + .enable = omap1_clk_enable_dsp_domain, + .disable = omap1_clk_disable_dsp_domain, +}; + +/* XXX SYSC register handling does not belong in the clock framework */ +static int omap1_clk_enable_uart_functional_16xx(struct clk *clk) +{ + int ret; + struct uart_clk *uclk; + + ret = omap1_clk_enable_generic(clk); + if (ret == 0) { + /* Set smart idle acknowledgement mode */ + uclk = (struct uart_clk *)clk; + omap_writeb((omap_readb(uclk->sysc_addr) & ~0x10) | 8, + uclk->sysc_addr); + } + + return ret; +} + +/* XXX SYSC register handling does not belong in the clock framework */ +static void omap1_clk_disable_uart_functional_16xx(struct clk *clk) +{ + struct uart_clk *uclk; + + /* Set force idle acknowledgement mode */ + uclk = (struct uart_clk *)clk; + omap_writeb((omap_readb(uclk->sysc_addr) & ~0x18), uclk->sysc_addr); + + omap1_clk_disable_generic(clk); +} + +/* XXX SYSC register handling does not belong in the clock framework */ +const struct clkops clkops_uart_16xx = { + .enable = omap1_clk_enable_uart_functional_16xx, + .disable = omap1_clk_disable_uart_functional_16xx, +}; + +long omap1_clk_round_rate(struct clk *clk, unsigned long rate) +{ + if (clk->round_rate != NULL) + return clk->round_rate(clk, rate); + + return clk->rate; +} + +int omap1_clk_set_rate(struct clk *clk, unsigned long rate) +{ + int ret = -EINVAL; + + if (clk->set_rate) + ret = clk->set_rate(clk, rate); + return ret; +} + +/* + * Omap1 clock reset and init functions + */ + +#ifdef CONFIG_OMAP_RESET_CLOCKS + +void omap1_clk_disable_unused(struct clk *clk) +{ + __u32 regval32; + + /* Clocks in the DSP domain need api_ck. Just assume bootloader + * has not enabled any DSP clocks */ + if (clk->enable_reg == DSP_IDLECT2) { + printk(KERN_INFO "Skipping reset check for DSP domain " + "clock \"%s\"\n", clk->name); + return; + } + + /* Is the clock already disabled? */ + if (clk->flags & ENABLE_REG_32BIT) + regval32 = __raw_readl(clk->enable_reg); + else + regval32 = __raw_readw(clk->enable_reg); + + if ((regval32 & (1 << clk->enable_bit)) == 0) + return; + + printk(KERN_INFO "Disabling unused clock \"%s\"... ", clk->name); + clk->ops->disable(clk); + printk(" done\n"); +} + +#endif |